The cat litter box liner of this invention is designed to extend the useful life of the litter in the litter box by screening the litter of fecal matter. It has been the common practice to provide a litter box or tray for household cats which have limited opportunity to take care of their biological demands outside. The litter box is conventionally a metal or plastic open container with a flat bottom and low, often sloping sides. Some modern litter boxes have a curved deflection screen mountable around the rim of the box to prevent litter from being cast out of the box during the instinctive coverup of excrement by a cat.
Litter used in the litter box is usually a granular material that is highly absorbant. One preferred material is diatomacious earth. Generally, the litter becomes quickly contaminated with fecal matter that emits a noxious odor before the absorbant properties of the litter are fully utilized. Often at this point a cat will refuse to use the box. It is the present practice to simply discard the litter when this occurs and refill the box with fresh litter.